More applications of winding numbers | Algebraic Topology 13 | NJ Wildberger

Описание: We define the degree of a function from the circle to the circle, and use that to show that there is no retraction from the disk to the circle, the Brouwer fixed point theorem, and a Lemma of Borsuk.

This is the 13th lecture of this beginner's course in Algebraic Topology, given by Assoc Prof N J Wildberger at UNSW.

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